The present invention relates to a turnbuckle comprising two adjusting rods or setting bars, an angular or miter gear consisting of gear elements, bearing elements for said gear elements and a casing surrounding these rods and said elements, said casing having a longitudinal or longer axis, the gear elements of said gear and said rods being situated along said longitudinal axis, thread means, said adjusting rods and said axial gear elements being connected by said thread means.
In an earlier turnbuckle of this kind with a bevel gear miter wheel gearing, the casing for transmission of the forces between the adjusting rods is divided either in longitudinal or in transverse direction and the resulting casing elements are joined together by a number of screws, rivets or the like.
In another kind of turnbuckle containing a miter gear, the forces between the adjusting rods are transmitted by an actuating rod extending coaxially through a one-piece or integrally formed casing and connecting the adjusting rods to one another U.S. Pat. No. Ser. 2,822,199(US-PS). Thereby the casing surrounding the adjusting rods merely forms a shell or cover surrounding the gear parts, whereas the tension or pressure forces of the adjusting or setting rods are taken up by the actuating rod which is connected to the adjusting rods by means of threads which can result in weak points in the toothed or grooved area of the actuating rod.
It is the object of the invention to improve turnbuckles containing miter gears in such a manner that they resist or withstand very great forces or strains and that can be very easily produced and maintained.
According to the present invention, this object is achieved by providing a casing consisting of one piece and provided with holding means for fixing the gear elements, the bearing elements and the adjusting rods. The casing encloses the gear elements and the bearing elements and is adapted to transfer the forces between the adjusting rods. The casing is also provided with at least one opening adapted for inserting the gear elements into the casing.
Because of the fact that the one-piece casing of the turnbuckle is dimensioned so that it can take up the forces between the adjusting rods and that the gear elements can be easily mounted, the casing maybe formed in a particularly simple manner e.g. from a single aluminum or steel block by boring out or milling out or reaming. Thus the whole turnbuckle can resist particularly high forces, strains or loads. Also, the gear elements are very well protected against external mechanical strains by the particularly sturdy construction of the casing. This construction further results in very low maintenance costs or in a maintenance-free operation by the selection of appropriate materials.
The fundamental or basic idea of the turnbuckle of the present invention is that it is practically designed and produced like a conventional turnbuckle, i.e. that the tension and pressure forces between the adjusting or setting rods are transmitted or guided cover the outer casing or sleeve and that at the same time, it is actable via a miter gear by a laterally applicable wrench, particularly a(n) (electrical) torque wrench, without twisting the ropes, chains, bars or the like to be connected.
One embodiment of the present invention includes a lateral gear wheel that is well supported, on the one hand, and easily accessible, on the other hand, and can be particularly easily inserted into the casing. The embodiment is characterized in that the insertion opening for at least one of the gear elements is opposed to the shoulder bearing of the lateral gear and is optionally closed by a plug-in cap or a threaded cap.
The mounting or assembling of the miter gear in the one-piece casing is further facilitated by the fact that the gear elements extending in the longitudinal direction of the one-piece casing of the turnbuckle are secured by recessed bearing sleeves screwed into the casing, while the axial bearing sleeves for securing the adjusting rods and the axial gear elements contain feather keys or securing screws to protect them against distortion.
The external ends of the adjusting rods ran thus form a cardan joint or a universal joint together with the supporting eyes to assure an extremely favorable adaptability of the mechanism of the adjusting rods or setting bars and the supporting eyes.
According to a further preferred feature of the invention, the production of the turnbuckle can be greatly facilitated by forming the openings provided in the one-piece casing as a single longitudinal bore and a single transversal bore. The bores in the casing can be recessed for the forming of bearing shoulders.